Binding compound derived from hardwood tar



Patented Aug. 6, 1940 I UNITED. STATES BINDING, COIMPOUND DERIVED FROM HARDWOOD Jean Levesque, Montreal, Quebec, Canada, as-

signor to The Province of Quebec, Department of Colonization, Quebec, Quebec, Canada No Drawing. Application July 24,

. Serial No. 286,215

5 Claims.

The present invention pertains to a novel binding compound adapted for use in road binding and for other purposes where a good and inex pensive binder is required.

The principal object of the present invention is to obtain a satisfactory and economical binder, similar to asphaltic cements, from derivatives of hardwood tar.

Briefly stated, the invention consists in combining hardwood pitch with non-volatile or slow- 1y volatile oils to produce a binder that is practically non-volatile at ordinary temperatureywith good penetration, good ductility and. other properties required in a good binder.

The ingredients employed according to the invention are defined as follows:

Hardwood settled tar pitch is the residue obtained by distilling hardwood settled tar, the end point of the distillation being between 235 C. and 285 C. at atmospheric pressure according to the desired products. a

Hardwood settled tar pitch oils are oils obtained by distilling hardwood settledtar pitch under reduced pressure, thus substantially preventing the destruction of valuable products in the pitch. For example, under absolute pressure of 20 millimeters of mercury, 100 parts by weight of hardwood settled tar pitch yield by distillation (up to 350 C.) more than 50 parts by weight of oils called hardwood settled tar pitch oils.

tained by distilling the pyroligneous acid, the end .point of the distillation being between 190 C. and 280 C. according to the desired products. Hardwood soluble tar pitch oils are oils obtained by distilling hardwood soluble tar pitch under reduced pressure, thus substantially preventing the destruction of valuable products in these oils. For example, 100 parts by weight of hardwood soluble tar pitch yields, by distillation under an absolute pressure of 20 millimeters of mercury, more than .50 parts by weight of hardwood soluble tar pitch oils.

In making the binder, one of the pitch oils or a mixture thereof, obtained as described above, is heated to distill ofi about one-fifth of the fluid, the remaining four-fifths being practically non-volatile at room temperature. To 375 grams of those non-volatile oils areadded 100 grams mixture is heated and stirred until, a thorough mixture of the properrconsistency is obtained. The resulting product is a non-volatile binder practically fulfilling the requirements of as- .phaltic cements for road binding purposes. Variable amounts of other hardwood tar oils boiling between 80 C. and 280 C. under atmospheric pressure may be added to produce a rapid, me-

Hardwood soluble tar pitch is the residue obble tar pitch or a mixture of both pitches. The;

dium or slow curing binder, according to requirements.

The proportions of ingredients herein mentioned may vary within wide limits. For ex-' ample, for one part of the pitch, by weight, there may be one to ten parts of pitch oil but in any case the resulting product is a practically non-volatile binder at ordinary temperature with good penetration, good ductility and other properties required in a good binder; I g

The invention is not limited to the specific ingredients and proportions named herein and is susceptible of variation within'the scope, of the appended claims.

What'I claim is:

1. The method of producing binding compounds from hardwood tar consisting in adding one to ten parts by weight of hardwood pitch oils to one part by weight of hardwood pitch, said oils being derived by distillation from hardwood tar pitch and having a distillation range comprised between'170 C.-and 360 C. under an absolute pressure of,20 millimeters of mercury. 2. The method of producing binding compounds from hardwood tar consisting in mixing oneto ten parts by weight of hardwood pitch oils with one part by weight of hardwood pitch and less than tenparts .by weight of hardwood tar oils boiling between 80 C. and 280 C. under atmospheric pressure, the hardwood pitch oils having a boiling range between 170 C. and 360 C(under an absolute pressure of 20 millimeters of mercury.

3. A binding composition comprising one to ten parts by weight of hardwood pitch oils and one part by weight of hardwood pitch, said distillation pitch oils being derived by distillation from hardwood tar pitch and having a range between 170 C. and 360 C. under an absolute pressure of 20 millimeters of mercury.

4. A binding composition comprising one to ten parts by weight of hardwood pitch oils, one part of hardwood pitch and less than ten parts by weight of hardwood tar oils having a boiling range between 80 C. and 280 C. under atmospheric pressure, the hardwood pitch oils having a boiling range between 170 C. and 360 C. under an absolute pressure of 20 millimeters of mercury.

5. A binding compound comprising approxihardwood pitch between170 C. and 360 C.

under an absolute pressure of 20 millimeters of mately 375 parts by weight of hardwood pitch mercury, and said tar oils boiling between v 

